Field of the Invention
The present invention relates to an image-forming apparatus that forms an image on a long sheet by transferring and fixing toner images on the long sheet, and an image-forming system using the image-forming apparatus.
Description of Related Art
An image-forming apparatus adopting an electrophotographic system such as a printer, a copier or the like has been known in the past. In such an image-forming apparatus, when forming the image(s) on a long sheet, the long sheet may remain on a paper-conveying route even after the image has been formed.
Such an image-forming apparatus has a fixing device for fixing the toner images transferred on the long sheet by heating under pressure. The fixing device includes a pair of rollers, a belt and rollers and the like. The fixing device nips the long sheet with any pressure being applied to it and heats the rollers and the like by a heater which generates heat by energization.
Since the long sheet is still present on the paper-conveying route in such an image-forming apparatus after the image has been formed, any marks may be leaved on the long sheet by heat or the long sheet may be deformed by heat when the rollers and the like of the fixing device contacts the long sheet after the image has been formed while the rollers and the like have been not sufficiently cooled.
Accordingly, Japanese Patent Application Publication No. 2008-233770 has proposed a technology such that the rollers and the like of the fixing device are released from the long sheet after the image has been formed and the rollers and the like of the fixing device and the long sheet are prevented from contacting to each other by inhibiting the long sheet from being bent.